Professor Emeritus at the University of Hong Kong, directing Education Policy Unit, Faculty of Education. He was Dean of Education, and Vice-President of the University. He has been visiting professors in various universities, including Harvard Graduate School of Education 1996-2006. He was a school teacher and a principal before he pursued doctoral study at the London Institute of Education. He has been consultant with most of the major international agencies, and involved in policy-related projects in various jurisdictions. His current attention is on the fundamental changes in society and their challenges to education, and focuses on learning as the core business of education.